OF ThflC U N I VER.5ITY OF I LLi NOIS v51Q& Return this book on or before the Latest Date stamped below. A charge is made on all overdue books. University of Illinois Library Digitized by the Internet Archive in 2011 with funding from University of Illinois Urbana-Champaign http://www.archive.org/details/phylogenyofhemip16spoo ILLINOIS BIOLOGICAL MONOGRAPHS Volume XVI PUBLISHED BY THE UNIVERSITY OF ILLINOIS URBANA, ILLINOIS EDITORIAL COMMITTEE John Tiieouore Buchholz Fred Wilbur Tanner Harley Jones Van Cleave T74. S- TLL- /, it* TABLE OF CONTENTS Nos. 1-2. The Turtles of Illinois. By Alvin R. Cahn. No. 3. The Phylogeny of the Hemiptera, Based on a Study of the Head Capsule. By Charles Stockman Spooner. No. 4. A Classification of the Larvae and Puparia of the Syrphidae of Illinois, Exclusive of Aquatic Forms. By Elizabeth M. Heiss. <:' l U l / i ILLINOIS BIOLOGICAL MONOGRAPHS Vol. XVI No. 3 -.XT' .•& ^ 5&S Published by the University of Illinois Under the Auspices of the Graduate School Urbana, Illinois EDITORIAL COMMITTEE John Theodore Buchholz Fred Wilbur Tanner Harley Jones Van Cleave UNIVERSITY LLINOIS 1000—4-38—12400 " MSiV THE PHYLOGENY OF THE HEMIPTERA BASED ON A STUDY OF THE HEAD CAPSULE WITH 24 PLATES BY Charles Stockman Spooner Contribution from the Entomological Laboratories of the University of Illinois No. 198 THE UNIVERSITY OF ILLINOIS PRESS URBANA 1938 f,(^ CONTENTS Introduction 7 Acknowledgments 8 Materials and Methods 8 The Generalized Hemipterous Head 10 Modifications of the Parts of the Head in Homoptera . 13 Phylogeny of the Homoptera 22 The Generalized Heteropterous Head 24 Modifications of the Parts of the Head in Heteroptera . 27 Phylogeny of the Heteroptera 37 Summary 41 Bibliography 45 Plates 51 INTRODUCTION The head of the Hemiptera is a highly modified structure. It is not surprising, after comparing it with the head of a generalized, mandi- bulate insect, to find that there has been considerable controversy regard- ing the identity of the various sclerites involved. The problem of the homology of these sclerites was practically hopeless until we obtained some direct evidence from embryology. The early work of Heymons ( 1899) gave us our first clue. This work was later corroborated and extended by Muir and Kershaw (1911, 1912). Further careful studies of the musculature of the various parts by Muir (1926) and Snodgrass (1921, 1928, 1935) have given us a fairly secure foundation upon which to base comparative studies. Careful and intensive studies of various species have recently been made: Nepa, Hamilton (1931): Xaucoris chnicoides, Becker (1929); Psylla mali, Weber (1929). Nevertheless the head in various Hemiptera has quite a variable structure, and in many cases superficially similar parts have been misinterpreted. It was with the hope of indicating some of these misinterpretations and thereby gaining some indication of the phylogeny of the group that this study was undertaken. It was thought that a study of the nymphs would aid in the understanding of some of the adult structures, and an effort was made to obtain and study as many nymphal forms as possible. The author is fully aware of the impossibility of showing the true phylogeny by a study of a limited group of characters and of the dangers of misinterpretation involved. There is no intention of claiming finality for the suggestions made. Results will be discussed in relation to the findings of other workers using other sets of characters. The characteristics presented by the head capsule of the Hemiptera appear to be a particularly valuable record for phylogenetic studies because, throughout the order, there has been little modification of func- tion. Hence the structural differences which accompany changes in function are reduced to a minimum. One or two interesting exceptions to this statement will be described later. Very little attention has been paid to the mouth parts in this work because they are pretty much of the same pattern throughout the order. The mandibles and maxillae are discussed as a means of identifying the fixed parts of the head. The types of mandibular levers have been studied to determine their phylogenetic value. The terms applied to the various parts are, so far as possible, those which have been in general use. The general nomenclature of MacGil- livray (1923b) or Snodgrass (1935) has been followed. New terms or new applications of old ones have been suggested for parts previously 8 ILLINOIS BIOLOGICAL MONOGRAPHS incorrectly named or where systematists have applied different terms for the same structure in the two suborders. ACKNOWLEDGMENTS This study was begun under the late Professor A. D. MacGillivray, and the author is greatly indebted to him for help and inspiration. It has been completed under Professor W. P. Hayes, and to him, likewise, the author is indebted for constant help and encouragement. Some of the specimens used in this study were obtained from the collections of the Illinois State Natural History Survey. I am indebted to the late Professor S. A. Forbes and to Dr. T. H. Frison and Dr. H. H. Ross for these courtesies. Among the most interesting of these materials were nymphs of the enicocephalid, Systelloderus biceps (Say) and of the ceratocombid, Ceratocombus vagans McA and Mai. These were loaned through the courtesy of Dr. Ross and, so far as I have been able to dis- cover, are the first nymphs of these families on record. The author has since taken two specimens of the nymphs of Ceratocombus vagans from the University Woods at Urbana, Illinois. The author also wishes to thank Professor H. B. Hungerford for gifts of specimens of Naeogeus burmeisteri L. and S. and Ochtems viridifrons Champ. Mr. H. E. McClure kindly furnished some specimens of Systel- loderus biceps. Mr. Walter Scruggs has spent many hours in arranging and photographing the plates, for which work the author is very grateful. MATERIALS AND METHODS Studies were made of representatives of all of the North American families in which material was available. Nymphs as well as adults were studied in every case in which they were obtainable, and this represents a surprisingly large proportion of the families. The heads were treated in ten per cent caustic potash until they were fairly clear and were then studied under the binocular microscope. It was found that the details were most readily seen in heads that were preserved and studied in glycerine. This had the further advantage of keeping them soft and flexible. The mandibular levers were dissected from heads that had been thoroughly treated in the potash. The larger forms were then cleared in carbolxylol and mounted in balsam, while the smaller forms were studied in a drop of glycerine. The following representatives of the various families were studied. The names are those used in Blatchley's Heteroptera of Eastern North America (1926), or Britton's Hemiptera of Connecticut (1923), or VanDuzee's Catalog of the Hemiptera of North America (1917). PHYLOGENY OF HEM1PTERA—SP00NER HOMOPTERA FULCORIDAE ClCADIDAE Otioccrus degerrii Kby. Tibicen sayi (Sm. and Grsb.) adult Otiocerus wolfii Kby. and nymph Amaloptera uhleri VanD. Lamenia vulgaris (Fitch) ClCADELLIDAE Cyarda melichari VanD. Agallia constricta VanD. Acanalonia sp. nymph Oncometopia undata (Fabr.) Acanalonia latifrons (Walk.) Gypona Ormenis pruinosa (Say) sp. nymph Jassus olitorius Say adult Pelitropis rotatula VanD. and nymph Phlepsius excultus (Uhl.) Oliarus vicarius (Walk.) Erythroneura comes (Say) Catonia impunctata (Fitch) Acinopterus acuminatus VanD. Cixius pini Fitch Euscelis bicolor (VanD.) Epiptera sp. nymph Cyrpoptus reineckei VanD. Aphididae Liberniella ornata (Stal) nymph Pentagramma vittatifrons (Uhl.) Lachnus sp. adult and nymph Dictyophora florens (Stal) Psyllidae Bruchomorpha sp. adult and nymph Pachypsylla celtidis-mamma Riley Cercopidae Trioza tripunctata (Fitch) Lepyronia quadrangularis (Say) adult and nymph Aleyrodidae Monecophora bicincta (Say) Trialcyrodes sp. HETEROPTERA Belostomatidae Veliidae Belostoma flumineum Say adult and Rhagovelia obesa Uhl. adult and nymph nymph Nepidae Mesoveliidae Ranatra americana Mont, adult and Mesovelia nymph bisignata Uhl. Nepa apiculata Uhl. adult and nymph Hydrometridae Naucoridae Hydrometra martini Kirk Pelocoris femoratus P. deB. adult and nymph Naeogeidae Naeogcus burmeisteri L. and S. adult Notonectidae and nymph Notonecta sp. adult and nymph OCHTERIDAE Corixidae Ochterus americanus (Uhler) adult Corixa sp. adult and nymph and nymph Gerridae Ochterus viridifrons Champ. Gerris marginatus Say adult and nymph Nerthridae Gerris remigus Say Gelastocoris sp. adult and nymph Ill ILLINOIS BIOLOGICAL MONOGRAPHS Saldidae Neididae Lamprocanthia sp. adult and nymph Ncides muticus (Say) adult and P.cntacora sp. nymph Jalysus spinosus (Say) Anthocoridae Corizidae Triphleps insidiosa (Say) adult and Corizus sp. adult and nymph nymph Harmocstes rcftexulus (Say) ClMICIDAE Leptocoris trivittatus Say adult and nymph Cimex lectularius Linn, adult and nymph CoREIDAE Anasa tristis (DeG.) adult and nymph Reduviidae Acanthocephala tcrminalis Dallas Sinea sp. adult and nymph Emesa brevipennis (Say) adult and Alydidae nymph Alydits sp. adult and nymph Mclanolcstes abdominalis H.-S. Piesmidae Nabidae Piesma cincrea Say Nobis subcolcoptratus Kirby adult TlXGITIDAE and nymph Corythuca ciliata Say adult and nymph Enicocephalidae Systelloderes biceps (Say) adult and Phymatidae nymph Phymata sp. adult and nymph Crvptostem matidae Akadidae Aneurus sp. adult and nymph Ceratocombus vagans McA. and M.